Glossary: C
calibrate
To fine-tune video levels for maximum clarity during recording or digitizing (from videotape).
Capture Mask effect
An effect that converts the format of source data during playback. For example, it could convert video frame data between PAL (25áfps) and NTSC (29.97áfps) formats.
CCIR
ComitΘ Consultatif International des Radio Communications. A mainly European organization similar to SMPTE (Society of Motion Picture and Television Engineers) in the United States that includes user and vendor representatives. Now called ITU (International Telecommunication Union).
See also ITU-R 601.
CCIR-601
See ITU-R 601.
change list
A list of instructions produced by Film Composer that is used to track and compare the differences between two versions of a digital sequence. A change list is used to update a work print cutting with specified new edits and revisions.
channel
1.  A physical audio input or output.
2.  One of several color components that combine to define a color image. An RGB image is made up of red, green, and blue color channels. In color correction, you can redefine color channels by blending color components in different proportions.
3.  See track.
character generator
An electronic device, or a computer device and software combination, that creates letters and numbers that can be superimposed on video footage as titles.
chassis
The housing for removable disk modules. The chassis contains a power supply, drives, and connectors for each module.
chroma
Video color.
See also chrominance.
ChromaCurve
A trademark of Avid Technology, Inc. ChromaCurve graphs appear in the Color Correction tool and are used to adjust the color values in a sequence. The graphs plot input values on the horizontal axis and output values on the vertical axis. The background color in the graph represents the color adjustment in the corrected sequence, and the curve on the graph (created by the user) increases or decreases the amount of that color in the corrected sequence.
chroma key
A method of combining images or parts of images from two different sources by replacing a solid color in one source with a picture from the second source.
ChromaWheel
A trademark of Avid Technology, Inc. ChromaWheel controls appear in the Color Correction tool and are used to adjust hue and saturation in a sequence. ChromaWheel controls provide an adjustment method that is similar to the physical controllers on traditional color correction equipment, with the addition of a color background that graphically represents the hue and saturation values being adjusted.
chrominance
The saturation and hue characteristics of a composite video signal; the portion of the video signal that contains color information. Adjust chrominance and other video levels before recording or digitizing.
See also chroma.
chunking
The transfer of media files in segments so other workgroup users can access and use the media before complete files have been sent.
cinching
Videotape damage due to creasing or folding.
circle take
A take from a film shoot that has been marked for use or printing by a circled number on the camera report.
clip
1.  A segment of source material recorded or digitized into your system at selected IN and OUT points and referenced in a project bin. The clip contains pointers to the media files in which the actual digital video and audio data is stored.
2.  In a record in a log, which stands for one shot, the clip includes information about the start and end timecode for the shot, the source tape name, and the tracks selected for editing.
3.  In OMFI, a general class of objects in the OMFáInterchange class hierarchy representing shared properties of source clips, filler clips, attribute clips, track references, timecode clips, and edge code clips. A clip is a subclass of a component.
See also master clip, media files, subclip.
clock timecode
See drop-frame timecode.
C-mode
A nonsequential method of assembly in which the edit decision list (EDL) is arranged by source tape number and ascending source timecode.
See also A-mode, B-mode, D-mode, E-mode, source mode.
codec
Compressor/decompressor. Any technology for compressing and decompressing data. Codecs can be implemented in both software and hardware. Some examples of codecs are: Cinepak, MPEG, and QuickTime.
color balance
The adjustment of the relative levels of color signals to produce the best quality image or effect.
color bars
A standard color test signal, displayed as a video pattern of eight equal width columns (that is, "bars") of colors. SMPTE color bars are a common standard. You adjust video levels against the color bars on your source videotape before recording or digitizing.
color correction
The process of adjusting the color characteristics of video material to achieve an accurate representation of color and consistency of color from one clip in a sequence to another. The term generally refers to adjustments made across all the video in a program rather than to individual color changes made as part of a single effect.
color frame
A sequence of video fields required to produce a complete pattern of both field and frame synchronization and color subcarrier synchronization. The NTSC system requires four fields; PAL requires eight.
color reference burst
The color synchronizing signal included as part of the overall composite video signal. When compared with the color subcarrier signal, the color reference burst determines the hue of the video image.
color timing
The process of selecting color and density values for a film before film printing.
color wheel
A circular graph that maps hue values around the circumference and saturation values along the radius. Used in the Color Correction tool as a control for making hue offset and secondary color correction adjustments.
component video
The structuring of the video signal whereby color and luminance signals are kept separate from one another using the color-subtraction method Y (luminance), B–Y (blue minus luminance) and R–Y (red minus luminance), with green derived from a combination. Two other component formats are RGB and YUV.
composite print
A film print containing both picture and sound.
composite sound track
A sound track containing all required sound elements — usually dialog, music, and effects mixed in correct proportions.
composite video
A video signal in which the luminance and chrominance components have been combined (encoded) as in standard PAL, NTSC, or SECAM formats.
compositing
The process of layering two or more images on top of one another. Examples include titles, keys, and picture-in-pictures.
composition
The standard term used by OMFáInterchange to refer to an edited sequence made up of a number of clips. The OMF equivalent of a sequence in an Avid system.
compression
1.  In audio, the process of reducing the dynamic range of the audio signal.
2.  In video, a lack of detail in either the black or the white areas of the video picture due to improper separation of the signal level.
3.  A reduction of audio signal detail, video signal detail, or both to reduce storage requirements during transformation from analog to Avid digital format. In JPEG compression, for example, algorithms for variable frame length analyze the information in each frame and perform reductions that maximize the information retained. Compression does not remove any frames from the original material.
See also lossless compression, lossy compression.
confidence value
A measurement, expressed as a percentage, of the probability that the pattern the system finds during a motion tracking operation is identical to the pattern for which the system is searching. During a motion tracking operation, Avid Symphony calculates a confidence value for each tracking data point it creates.
conform
To prepare a complete version of your project for viewing. The version produced might be an intermediate working version or the final cut.
conforming a film negative
The mathematical process that the editing system uses to ensure that the edits made on a videotape version of a film project (30áfps) are frame accurate when they are made to the final film version (24áfps).
Console window
A display that lists the current system information and chronicles recently performed functions. It also contains information about particular items you are editing, such as the shots in your sequence or clips selected from bins.
consolidate
To make copies of media files or portions of media files, and then save them on a drive. The Consolidate feature operates differently for master clips, subclips, and sequences.
contrast
The range of light-to-dark values present in a film or a video image.
control point
A location on a BΘzier curve that controls its direction. Each control point has two direction handles that can extend from it.
control track
The portion of the video recording used to control longitudinal motion of the tape during playback. Control track can be thought of as electronic sprocket holes on the videotape.
CPU
Central processing unit. The main computational section of a computer that interprets and executes instructions.
crash edit
An edit that is electronically unstable, such as one made using the pause control on a deck, or using a noncapstan served deck.
crash recording
See hard recording.
crawling text
Text that moves horizontally over time. Examples include stock and sports score tickers that appear along the bottom of a television screen.
cropping
The redefining of image boundaries, usually by electronically removing the top, bottom, left, or right sides of the image.
crossfade
An audio transition in which the outgoing sound gradually becomes less audible as the incoming sound becomes more distinct. Also called an audio dissolve.
See also dissolve, fade.
crushing the blacks
The reduction of detail in the black regions of a film or a video image by compressing the lower end of the contrast range.
CU
Close-up.
See also ECU.
cue
To shuttle a videotape to a predetermined location.
Curves graph
An X, Y graph that plots input color values on the horizontal axis and output color values on the vertical axis. Used in the Color Correction tool as a control for changing the relationship between input and output color values.
cut
1.  An instantaneous transition from one video source to another.
2.  A section of source or record tape.
cut list
A series of output lists containing specifications used to conform the film work print or negative.
See also dupe list.

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